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The manipulation and understanding of molecular transport across functionalized nanopores will take us closer to mimicking biological membranes and thus to design high-performance permselective separation systems. In this work, Surface-initiated atom transfer radical polymerization (SI-ATRP) of (2-methacryloyloxy)-ethyltrimethylammonium chloride (METAC) was performed on both mesoporous silica and mesoporous titania thin films. Pores were proven to be filled using ellipsometry and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Furthermore, the employed method leads to a polymer overlayer, whose thickness could be discriminated using a double-layer ellipsometry model. Cyclic voltammetry experiments reveal that the transport of electrochemically active probes is affected by the PMETAC presence, both due to the polymer overlayer and the confined charge of the pore-tethered PMETAC. A more detailed study demonstrates that ion permeability depends on the combined role of the inorganic scaffolds’ (titania and silica) surface chemistry and the steric and charge exclusion properties of the polyelectrolyte. Interestingly, highly charged negative walls with positively charged polymers may resemble zwitterionic polymer behavior in confined environments.

Mesoporous materials bear great potential for biotechnological applications due to their biocompatibility and versatility. Their high surface area and pore interconnection allow the immobilization of molecules and their subsequent controlled delivery. Modifications of the mesoporous material with the addition of different chemical species, make them particularly suitable for the production of bioactive coatings. Functionalized thin films of mesoporous silica and titania can be used as scaffolds with properties as diverse as promotion of cell growth, inhibition of biofilms formation, or development of sensors based on immobilized enzymes. The possibility to pattern them increase their appeal as they can be incorporated into devices and can be tailored both with respect to architecture and functionalization. In fact, selective surface manipulation is the ground for the fabrication of advanced micro devices that combine standard micro/nanofluids with functional materials. In this review, we will present the advantages of the functionalization of silica and titania mesoporous materials deposited in thin film. Different functional groups used to modify their properties will be summarized, as well as functionalization methods and some examples of applications of modified materials, thus giving an overview of the essential role of functionalization to improve the performance of such innovative materials.

The coherent manipulation of acoustic waves on the nanoscale usually requires multilayers with thicknesses and interface roughness defined down to the atomic monolayer. This results in expensive devices with predetermined functionality. Nanoscale mesoporous materials present a high surface-to-volume ratio and tailorable mesopores, which allow the incorporation of chemical functionalization to nanoacoustics. However, the presence of pores with sizes comparable to the acoustic wavelength is intuitively perceived as a major roadblock in nanoacoustics. Here, we present multilayered nanoacoustic resonators based on mesoporous SiO2 thin films showing acoustic resonances in the 5-100 GHz range. We characterize the acoustic response of the system using coherent phonon generation experiments. Despite resonance wavelengths comparable to the pore size, we observe for the first time well-defined acoustic resonances. Our results open the path to a promising platform for nanoacoustic sensing and reconfigurable acoustic nanodevices based on soft, inexpensive fabrication methods. Fil: López Abdala, Nicolás Andrés. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Esmann, Martin. Université de Paris-Saclay; Francia. Centre National de la Recherche Scientifique; Francia Fil: Fuertes, María Cecilia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes.; Argentina Fil: Angelome, Paula Cecilia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Constituyentes.; Argentina Fil: Ortiz, Omar. Université de Paris-Saclay; Francia. Centre National de la Recherche Scientifique; Francia Fil: Bruchhausen, Axel Emerico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentina Fil: Pastoriza, Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentina Fil: Perrin, Bernard. Sorbonne University; Francia. Centre National de la Recherche Scientifique; Francia Fil: Soler Illia, Galo Juan de Avila Arturo. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lanzillotti Kimura, Norberto Daniel. Université de Paris-Saclay; Francia. Centre National de la Recherche Scientifique; Francia

Múltiples aplicaciones científicas y tecnológicas requieren, hoy en día, del uso de sensores confiables y altamente sensibles. En este sentido, los nanomateriales han demostrado gran potencial, debido a su gran área específica y sus propiedades físico-químicas diferenciales. En particular, en los últimos años se ha comenzado a desarrollar sensores basados en la combinación de films delgados mesoporosos y nanopartículas metálicas. Estos nanomateriales compuestos integran en un solo sistema la gran área específica, el tamaño altamente controlado de poros y la sencillez de manipulación de los films delgados mesoporosos, con las propiedades ópticas de las nanopartículas metálicas. Esta tesis propone ahondar en el desarrollo de sistemas compuestos formados por films delgados mesoporosos y nanopartículas metálicas que puedan ser utilizados en sensado por Espectroscopía Raman Aumentada por Superficie (SERS). Adicionalmente y a partir del conocimiento de las propiedades SERS en relación a las características de los sistemas, este trabajo busca extender la utilización de esta técnica espectroscópica para la obtención de información sobre las características fisicoquímicas y estructurales de los sistemas compuestos sintetizados. Para ello, en una primera parte se presentan sistemas compuestos sintetizados a partir de films delgados mesoporosos de TiO2 y nanopartículas de Au, combinados en diferentes arquitecturas, para el estudio del efecto de sus propiedades estructurales sobre el sensado por SERS. El análisis se dividió en dos ejes. Por un lado, se estudió el efecto del posicionamiento de las nanopartículas en el material y cómo esto determina las capacidades del sensado de diferentes sondas modelo. Por otro lado, se evaluó la influencia de las características del film delgado mesoporoso sobre la síntesis de nanopartículas y sus consecuencias en el sensado por SERS. Los resultados indican que las características del film (espesor, tamaño y orden de los poros) controlan la cantidad, morfología y distribución de las nanopartículas. Asimismo, se evidencia que las capacidades de sensado en términos de reproducibilidad punto a punto, sensibilidad y límites de detección pueden ser controladas a partir del diseño del nanomaterial compuesto. En la segunda parte, se presentan varias estrategias sintéticas alternativas para la construcción de sensores SERS. En particular, se evaluaron las características estructurales de sistemas formados por nanopartículas de Au y Ag de distintas morfologías combinados con films mesoporosos puros, híbridos y/o consolidados por rayos X de alta intensidad. Los resultados permitieron establecer parámetros sintéticos para aumentar la estabilidad y sensibilidad de los sensores. Finalmente, se presentan sistemas ópticamente sensibles a pH que permiten monitorear los cambios producidos por una reacción modelo. De esta manera, en base al conocimiento adquirido, fue posible sentar las bases para la construcción de sensores SERS que permiten estudiar procesos dinámicos en ambientes confinados. Nowadays, multiple scientific and technological applications require the use of reliable and highly sensitive sensors. In this way, nanomaterials have shown great potential due to their large specific area and differential physicochemical properties. In particular, sensors based on the combination of mesoporous thin films and metal nanoparticles started to be developed in recent years. These composite nanomaterials integrate in a single system the large specific area, the highly controlled pore size and the simplicity of manipulation of the mesoporous thin films, with the optical properties of the metal nanoparticles. This thesis proposes to delve into the development of composite systems formed by mesoporous thin films and metal nanoparticles that can be used in sensing by Surface Enhanced Raman Spectroscopy (SERS). Additionally, from the knowledge of structural - SERS activity relations, this work seeks to extend the use of this spectroscopic technique to obtain information about the physicochemical and structural characteristics of the composite systems. In the first part, TiO2 mesoporous thin films and Au nanoparticles composite systems were synthesized in different architectures, to study the effect of their structural properties on SERS sensing. The analysis was divided into two axes. On one hand, the effect of the nanoparticles ́ position in the material over the sensing capabilities was studied, using different probe molecules. On the other hand, the influence of the mesoporous thin film characteristics over the nanoparticles synthesis and the consequences on SERS sensing were evaluated. The results indicate that the characteristics of the film (thickness, size and order of the pores) define the quantity, morphology and distribution of the nanoparticles. Likewise, it is shown that sensing capabilities in terms of spot-to-spot reproducibility, sensitivity and detection limits can be controlled from the composite material design. In the second part, several alternative synthetic strategies for the construction of SERS sensors are presented. In particular, the structural characteristics of systems formed by Au and Ag nanoparticles of different morphologies combined with pure, hybrids and/or consolidated by high intensity X-rays mesoporous films were evaluated. The results allowed to establish the synthetic parameters to increase the stability and sensitivity of the sensors. Finally, optically sensitive pH systems that allow monitoring the changes produced by a model reaction are presented. In this way, based on the acquired knowledge, it was possible to pave the way towards the construction of SERS sensors that allow the study of dynamic processes in confined environments. Fil: Zalduendo, María Mercedes. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

This research was performed to obtain high-value products from clay materials. High-grade nanometric delta-alumina (&delta, Al2O3) was obtained from the modification of clay-based minerals, which could be potentially applied in the form of thin film for novel optoelectronic applications. The selective recovery process of alumina from clay materials presents an important advantage regarding the complete removal of other starting constituents such as silica, iron, titanium, alkali, and alkaline earth metals. To accomplish the selective removal of different species, an acid leaching route was used to extract the aluminum, then the iron impurities were eliminated by alkaline precipitation. The solution was acidized to precipitate the aluminum as aluminum chloride hexahydrate. Finally, the aluminum chloride hexahydrate was calcinated to obtain nano-delta-alumina with purity of over 98.5% Al2O3. The dominating crystalline phase was delta&ndash, gamma alumina (&delta, phase and &gamma, phase), with a particle size of &lt, 140 nm. Then, these nanoparticles (NPs) were prepared as a stable colloidal dispersion to form a mesoporous layer employing the spin-coating technique. Initially, the synthesized alumina was characterized by atomic force microscopy (AFM) and TEM to determine the particle size and its morphology, whereas the colloidal dispersion was analyzed by rheological measurements. Finally, the findings of this investigation made it possible to get thin films with good porosity, which can be used in optoelectronic applications, specifically in perovskite solar cells.

Mesoporous oxide thin films (MOTF) present very high surface areas and highly controlled monodisperse pores in the nanometer range. These features spurred their possible applications in separation membranes and permselective electrodes. However, their performance in real applications is limited by their reactivity. Here, we perform a basic study of the stability of MOTF toward dissolution in aqueous media using a variety of characterization techniques. In particular, we focus in their stability behavior under the influence of ionic strength, adsorption of electrochemical probes, and applied electrode potential. Mesoporous silica thin films present a limited chemical stability after electrochemical cycling, particularly under high ionic strength, due to their high specific surface area and the interactions between the electrochemical probes and the surface. In contrast, TiO₂ or Si0.9Zr0.1O₂ matrices present higher stability; thus, they are an adequate alternative to produce accessible, sensitive, and robust permselective electrodes or membranes that perform under a wide variety of conditions., Facultad de Ciencias Exactas, Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

The fluid-front dynamics resulting from the coexisting infiltration and evaporation phenomena in nanofluidic systems has been investigated. More precisely, water infiltration in both titania and silica mesoporous films was studied through a simple experiment: a sessile drop was deposited over the film and the advancement of the fluid front into the porous structure was optically followed and recorded in time. In the case of titania mesoporous films, capillary infiltration was arrested at a given distance, and a steady annular region of the wetted material was formed. A simple model that combines Lucas-Washburn infiltration and surface evaporation was derived, which appropriately describes the observed filling dynamics and the annulus width in dissimilar mesoporous morphologies. In the case of wormlike mesoporous morphologies, a remarkable phenomenon was found: instead of reaching a steady infiltration-evaporation balance, the fluid front exhibits an oscillating behavior. This complex filling dynamics opens interesting possibilities to study the unusual nanofluidic phenomena and to discover novel applications. Fil: Mercuri, Magalí. Comisión Nacional de Energía Atómica. Gerencia de Área de Investigación y Aplicaciones no Nucleares. Gerencia de Desarrollo Tecnológico y Proyectos Especiales. Departamento de Micro y Nanotecnología; Argentina Fil: Pierpaulli, Karina. Comisión Nacional de Energía Atómica. Gerencia de Área de Investigación y Aplicaciones no Nucleares. Gerencia de Desarrollo Tecnológico y Proyectos Especiales. Departamento de Micro y Nanotecnología; Argentina Fil: Bellino, Martin Gonzalo. Comisión Nacional de Energía Atómica. Gerencia de Área de Investigación y Aplicaciones no Nucleares. Gerencia de Desarrollo Tecnológico y Proyectos Especiales. Departamento de Micro y Nanotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Berli, Claudio Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina

Lityum geçiş metal oksitlerinin (LMO), enerji uygulamalarında büyük bir önemi vardır ve bu malzemelerin, suyun oksidasyon elektro-katalizörü olarak kullanılması da bu uygulamalardan bir tanesidir. Yüksek yüzey alanlarına sahip, mezoporlu LiMn2-xCoxO4 ince filmler, eriyik tuz destekli kendiliğinden oluşma (EDKO) metoduyla sentezlenebilir ve malzemeler doğal olarak daha fazla aktif yüzey bulundurur. Lityum, mangan(II), kobalt (II) nitrat tuzları, yüzey aktif maddeler olan CTAB ve P123 ve ek olarak nitrik asit ve etil alkol bulunduran homojen çözeltiler, dönel kaplama yöntemiyle bir substrat üzerine kaplanır ve liyotropik sıvı kristal (LSK) faz elde edilir ve bu faz, düşük açı X-ışını difraktometresi ile analiz edilebilir. Bu LSK faz, yüksek ısı ile oksitlenir ve mezoporlu LiMn2-xCoxO4 ince filmler sentezlenir. Kobalt x miktarı 0'dan 2'ye arttırılsa bile, malzemenin mezopor ve kristal yapısının korunduğu gözlenlenmiştir.İnce filmler, XRD, SEM, EDX, TEM, Azot adsorpsiyon teknikleri ile incelenmiştir. XRD tekniği, farklı orandaki malzemelerin spinel yapı oluşturduğu ve birim hücre parametrelerinin benzer olduğunu göstermiştir. LiMn2-xCoxO4 içindeki kobalt miktarının artmasıyla, malzemenin yüzey alanı 98'den 144 m2 g-1'a yükselmiştir. Ayrıca SEM tekniği ile de film kalınlıklarının 200 ile 500 nm arasında değiştiği gözlemlenmiştir.viLSK faz yardımıyla elde edişen ince filmler, FTO camlarının üzerine de kaplanmış ve su oksidasyon elektro-katalizörü olarak, elektrokimyasal karakterizasyon deneylerinde kullanılmıştır. Tüm elektrotlar, verimli katalizörler olarak nitelendirilmiştir. Fakat malzeme, LiMn2O4'dan LiMnCoO4 oranına götürülünce, Tafel eğrisi de 124'den 66 mV dec-1'e düşmüştür ve bu durum 1 mA cm-2 akımdaki 491 mV'dan 294 mV'a olan ek potansiyel düşüşü ile kanıtlanmıştır. Aynı zamanda LiMnCoO4 oranlı malzeme katalitik verimi ile ve 120 mA cm-2 akımda bile bozulmayan yapısıyla rapor edilmiştir.Mezoporlu LiMn2O4 ince film, ardışık iyonik katman adsorpsiyonu ve reaksiyonu (SILAR) yöntemi ile modifiye edilmiştir. Elektrot, 1M kobalt çözeltisine batırma yöntemi ile yapılmış ve bunun aracılığıyla yüzeyi LiMn2-xCoxO4 kompozisyonu olan malzeme elde edilmiştir. Bu modifiye, Tafel eğrisi değerinin 127'den 80 mV dec-1'e inmesini sağlamış fakat elektrotların stabil olmadığı gözlenmiştir. 20% kobalt ve 80% mangan içeren LiMn2-xCoxO4, SILAR yöntemi için substrat olarak kullanılmış ve modifiye 5 kereye kadar yapılmıştor. Tafel eğrisi değeri 64'ten 46 mV dec-1'e düşürülmüş ve ek potansiyel değerleri de 1 mA cm-2 akımda 304'ten 265'e, 10 mA cm-2'de 826'dan 546 mV'a düşüşlerle ve elektrodun stabil yapısıyla gösterilmiştir. The lithiated transition metal oxides (LMO) are important group of materials in energy applications, particularly as water oxidation electrocatalysts. The mesoporous LiMn2-xCoxO4 thin film has been synthesized by using molten-salt assisted self assembly (MASA) method with a high surface area. Homogenous ethanol solution of nitrate salts (lithium, manganese(II) and cobalt(II)) and surfactants (CTAB and P123) in the presence of a small amount of HNO3 is coated over a glass substrate by spin-coating to form lyotropic liquid crystal (LLC) mesophase that is calcined at elevated temperature to synthesize disordered mesoporous LiMn2-xCoxO4 thin film. The mesophases display diffraction line(s) at small angles, indicating an ordered structure. The cobalt amount (x) has been varied from 0 to 2, keeping the same mesoporous and crystal structures.The films were characterized using XRD, SEM, EDX, TEM, N2 adsorption-desorption techniques. The XRD provided that the end products have a spinel structure with very similar unit cell parameters in all compositions. The surface areas of the films vary from 98 to 144 m2/g with increasing cobalt amount in the films. The SEM images showed that the thin films are uniform with a thickness of around 200-500 nm.The LLC mesophases have been also coated over FTO glass to fabricate electrode for oxygen evolution reaction (OER) and also for electrochemical characterizations. The electrodes prepared from all composition performed as goodivelectrocatalysts, however the Tafel slope decreased from 124 to 66 mV dec-1 going from LiMn2O4 to LiMnCoO4. The overpotential also dropped from 491 mV to 294 mV at 1 mA cm-2 in water oxidation reaction. The LiMn2O4 is the worst electrocatalyst tested in this thesis. It has high Tafel slope, which is not desired and also not stable during electrochemical test. The stability improves with increasing cobalt in the films. The LiMnCoO4 has been reported to be one of the most efficient and stable electrocatalyst even if it is used 120 mA cm-2 current densities. Therefore, the electrode with this composition has been investigated in detail in an alkali media.The mesoporous LiMn2O4 thin film is modified by successive ionic layer adsorption and reaction (SILAR) method to improve its activity and stability. This electrode is dipped into a 1 M cobalt (II) solution, then washed several time to ensure a single layer of cobalt species on the surface, the modified electrode is calcined to produce cobalt rich LiMn2-xCoxO4 surface. Eventhough, the amount of cobalt in the modified electrode is smaller than 1 %, the modification decreased the Tafel slope from 127 to 80 mV dec-1, but the electrode was unstable during water oxidation process in alkali media. A range of LiMn2-xCoxO4 (x = 0 to 0.4) compounds were modified by the SILAR method and tested for OER. The mesoporous LiMn1.6Co0.4O4 (20 % cobalt and 80 % manganese) was used as the substrate and the SILAR method was employed 5-times, the Tafel slope of this electrode decreased from 64 to 46 mV dec-1 with an overpotential decrease from 304 to 265 mV at 1mA cm-2 and 826 to 546 mV at 10 mA cm-2 by modification and displayed a robust property in water oxidation process. 120

Fundamental investigations on photochemical and electronic properties of photocatalytically active electrodes require well-defined model systems. We designed ordered mesoporous thin films with uniform pore size distributions and homogeneous pore structures by combining a sol-gel process with evaporation induced self-assembly (EISA) and spin coating to synthesize mesoporous niobium pentoxide thin films on substrates for electrochemical characterization. The thin film production was optimized tuning the precursor solution and parameters like spin coating speed, relative humidity level during solvent evaporation and furnace temperature. The main aim of this work and the reason for using mesoporous films was to eliminate contact resistance with the electrode while allowing a maximum interface with the surrounding gas phase. This concept could be proved by impedance spectra featuring one semicircle solely. We found that temperatures above 350 C led to a linear increase of resistance over time. According to our hypothesis this is due to a diffusion process of oxygen vacancies originally located at the surface into the bulk material as well as due to the surface reaction. By consuming electrons as well as oxygen vacancies the amount of free charge carriers is reduced, thus increasing the measured impedance. By altering the measurement conditions we found that UV-irradiation, oxygen partial pressure variation and humidity level strongly influence the effective conductivity. This opens not only the field of photocatalytically active electrodes but also humidity and gas sensing as possible fields of application for the studied material.

Los óxidos mesoporosos presentan elevadas áreas específicas (200-1000 m^2/g) y poros ordenados monodispersos cuyo diámetro puede regularse entre 2 y 50 nm. Se han desarrollado hasta el momento una gran variedad de técnicas químicas suaves que permiten obtenerlos a partir de la combinación del autoensamblado de moléculas anfifílicas y reacciones sol-gel. Además, es posible combinar estos materiales con nanopartículas (NPs) metálicas, mediante diversas técnicas. Entre todas las posibles formas de procesamiento de estos óxidos, las películas delgadas mesoporosas (PDMs) son especialmente interesantes, ya que pueden integrarse en gran variedad de dispositivos electrónicos u ópticos. Esta tesis propone obtener PDMs de dióxido de titanio con porosidad y propiedades estructurales controladas y bien definidas, y utilizarlas como plataformas para estudiar el efecto del confinamiento en el transporte de moléculas y en reacciones químicas. En este trabajo, se obtuvieron PDMs de TiO2 con poros de diámetro entre 2 y 10 nm sobre vidrio conductor (ITO), silicio o vidrio mediante dip o spin-coating utilizando tres moldes de poros diferentes: los copolímeros tribloque Pluronic F127 y Pluronic P123, y la molécula dibloque Brij 58. Las películas se sometieron a diferentes tratamientos térmicos con el propósito de regular las propiedades finales del material poroso, que fueron debidamente caracterizadas. En particular, se profundizó y amplió la caracterización del sistema moldeado con Brij 58, muy acotado en bibliografía, el cual presenta tamaño de poros y espesor de pared menores que los materiales obtenidos a partir de copolímeros tribloque. Por lo tanto, representa una plataforma propicia para estudiar efectos de confinamiento. Se estudió el transporte de sondas electroquímicamente activas (Fe(CN)63-, Ru(NH3)63+ y Ferrocenometanol) desde la solución hacia el sustrato a través del sistema mesoporoso mediante voltametría cíclica (VC). Se encontró que existe un complejo mecanismo en el que hay que tener en cuenta caminos paralelos de adsorción superficial y transporte en la fase acuosa, que depende fuertemente de las dimensiones del sistema. Por espectroscopía de correlación de fluorescencia (FCS), en tanto, se logró describir cuantitativamente cómo la estructura y dimensiones de poros de las PDMs y la fuerza iónica modulan la difusión de una sonda fluorescente (Rodamina B). Por otra parte, se estudió el crecimiento de NPs de Au dentro de los sistemas de mesoporos. Se encontró que tanto la cantidad como el tamaño de las NP obtenidas depende marcadamente del tamaño de los poros y de su organización espacial. Finalmente, se evaluó la influencia de las características de las NPs formadas en una aplicación como sensores basados en espectroscopía Raman aumentada por superficie (SERS), encontrándose resultados prometedores. Los resultados obtenidos permitieron demostrar que es posible modular a escala nanométrica las dimensiones de las estructuras porosas a través del procesamiento de PDMs, y que esta modulación tiene relevancia tanto en el transporte como en la reactividad de diferentes especies químicas. Mesoporous oxides present large specific surfaces (200-1000 m2/g) and ordered monodispersed pores, whose diameter can be adjusted between 2 and 50 nm. Up to the present, a variety of soft chemical techniques have been developed to obtain these materials by combining evaporation induced self-assembly of amphiphilic molecules and sol-gel reactions. In addition, it is possible to combine these materials with metallic nanoparticles (NPs), using several techniques. Among all the ways of processing such oxides, mesporoporous thin films (MTFs) are particularly interesting, since they can be integrated into a wide variety of electronic or optical devices. This thesis proposes to obtain TiO2 MTFs with well-defined controlled porosity and structural properties, and to use them as platforms to study the effect of confinement on chemical reactions and molecules transport. In this work, TiO2 MTFs with pore diameter between 2 – 10 nm were deposited onto conductive glass (ITO), silicon or glass by dip or spin-coating using three different pore templates: triblock copolymers Pluronic F127 and Pluronic P123, and the diblock molecule Brij58. Films were exposed to different heat treatments in order to regulate the final properties of the porous material, which were properly characterized. In particular, the characterization of Brij 58 templated system, very scarce in the literature, was extended, since it represents an ideal platform to study confinement effects due to it’s the smaller pore diameter and wall thickness when compared with the triblock copolymers templated oxides. The transport of electrochemically active probes (Fe(CN)6 3-, Ru(NH3)6 3+ and Ferrocenemethanol) from the solution to the substrate through the mesoporous systems was studied by means of cyclic voltammetry (CV). The experiments demonstrated that a complex mechanism is involved in such transport, in which it is necessary to take into account parallel paths of superficial adsorption and transport in the aqueous phase. Moreover, the mechanism depends strongly on the system’s dimensions. Meanwhile, by using fluorescence correlation spectroscopy (FCS) it was possible to quantitatively describe how the structure and dimensions of the MTFs pores and the ionic strength modulate the diffusion of a fluorescent probe (Rhodamine B). On the other hand, the growth of Au NPs within mesoporous systems was studied. Both the quantity and the size of the obtained NPs depended markedly on the pores size and their spatial organization. Finally, the influence of the characteristics of those NPs in an application as sensors based on Surface Enhanced Raman Spectroscopy (SERS) was evaluated, with promising results. The results obtained in this work allowed demonstrating that it is possible to modulate the dimensions of porous structures at nanometric scale, through processing of MTFs. Moreover, this modulation is relevant for molecular transport and reactivity of different chemical species. Fil: Steinberg, Paula Yael. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Zr–Si mixed mesoporous oxides were obtained in a wide range of proportions, from 0 to 30% and from 70 to 100% of Si, using Si(OEt)4 and ZrCl4 as precursors and Pluronic F127 as a template. The oxide mesostructure was characterized by transmission electron microscopy and 2D-small angle X-ray scattering. Fourier transform infrared spectroscopy measurements suggested a local homogeneous interdispersion of both cations. Further selective studies using X-ray Absorption Near Edge Structure (XANES) spectroscopy for separately Zr and Si local environments, allowed for demonstrating that the Zr coordination varies from close to 7 to 6, when its concentration in the mixed oxide is reduced. In addition, it was possible to determine that in mixed oxides with low Zr concentrations, Zr can fit into the spaces occupied by Si in SiO2 pure oxide. An equivalent XANES result was obtained for Si, which is also compatible with the information obtained by FTIR. Furthermore, the Zr–O distance varied from close to 2.2 Å to 1.7 Å when the Zr concentration decreased. Finally, our study also demonstrates the usefulness of XANES to selectively assess the local structure (coordination, symmetry and chemical state) of specific atoms in nanostructured systems. Fil: Andrini, Leandro Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina Fil: Angelome, Paula Cecilia. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Soler Illia, Galo Juan de Avila Arturo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Inorgánica, Analítica y Química Física; Argentina. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Requejo, Felix Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina

Mesoporous thin films of transition metal lithiates (TML) belong to an important group of materials for the advancement of electrochemical systems. This study demonstrates a simple one pot method to synthesize the first examples of mesoporous LiCoO2 and LiMn2O4 thin films. Molten salt assisted self-assembly can be used to establish an easy route to produce mesoporous TML thin films. The salts (LiNO3 and [Co(H2O)6](NO3)2 or [Mn(H2O)4](NO3)2) and two surfactants (10-lauryl ether and cethyltrimethylammonium bromide (CTAB) or cethyltrimethylammonium nitrate (CTAN)) form stable liquid crystalline mesophases. The charged surfactant is needed for the assembly of the necessary amount of salt in the hydrophilic domains of the mesophase, which produces stable metal lithiate pore-walls upon calcination. The films have a large pore size with a high surface area that can be increased up to 82 m2 g−1. The method described can be adopted to synthesize other metal oxides and metal lithiates. The mesoporous thin films of LiCoO2 show promising performance as water oxidation catalysts under pH 7 and 14 conditions. The electrodes, prepared using CTAN as the cosurfactant, display the lowest overpotentials in the literature among other LiCoO2 systems, as low as 376 mV at 10 mA cm-2 and 282 mV at 1 mA cm-2. The authors thank the Scientific and Technological Research Council of Turkey (TÜBİTAK) under project number 113Z730 for financial support. Ö.D. is a member of Science Academy, Istanbul.

Bu tez, bir tuz ve yüzeyaktiflerin kendi kendine oluşumunu esas alan ve eriyik tuz yardımlı kendiliğinden oluşma (EYKO) yöntemi olarak tanımlanan yöntemle, mezogözenekli CdTiO3 ince filmlerin sentezi ve karakterizasyonu üzerine odaklanmaktadır. EYKO yöntemi, mezogözenekli şeffaf ince filmlerin üretilmesi için uygun bir yöntemdir. Yakılmış edilmiş tozun ve jel numunelerinin karakterizasyonu x-ışını kırınımı (XRD), taramalı elektron mikroskobu (SEM), geçirimli elektron mikroskopisi (TEM), zayıflatılmış toplam yansıma (ATR-IR), azot adsorplama/desorplama ve polarize optik mikroskop (POM) teknikleri kullanılarak yapılmıştır.İstenilen malzemenin hazırlanabilmesi için ilk adım; çözücü olarak etil alkolün kullanılmasıyla ve iki farklı yüzeyaktifle (bir üçblok kopolimer, P123, ve C16H33N(CH3)3Br, CTAB) birlikte, [Cd(H2O)](NO3)2 tuzunun, titanya kaynağı olarak titanyum(IV)bütoksit'in (Ti(OC4H9)) ve titanyum alkoksidin hızlı polimerizasyonunu önlemek için asit olarak HNO3'ün karıştırılmasıyla berrak bir çözeltinin oluşturulmasıdır. Yüzeyaktiflerin hidrofilik alanlarının yönlendirilmesi ile hidrolize titanyum ürünleri ve eriyik tuz tarafından bir sıvı kristalin mezofazın oluşturulması için, hazırlanan berrak çözelti cam alttaş üzerine kaplandı. Jel numunelerinin yakılması ile, mezo-gözenekli CdTiO3 materyali üretildi. Bu tez çalışması kapsamında, en uygun tuz:yüzeyaktif oranı, asit miktarı, yüzey aktif madde oranı, kaplama yöntemi ve kalsinasyon rotasını belirlemek için çeşitli parametreler değiştirildi.Daldırma ve çekme kaplama, dönğülü kaplama ve dökme yöntemleri arasında daldırma ve çekerek kaplama yöntemi, daha az yan ürünle (ağırlıklı olarak CdO) malzeme üretmek için daha iyi sonuçlar verdi. Çözeltiye eklenen HNO3 miktarı, hazırlanan jel filmlerin homojenliğini ve stabilitesini etkilemektedir. HNO3 miktarının değiştirilmesinin yüzey alanını önemli ölçüde etkilememesine rağmen, aşırı miktarda asit ilavesiyle yakılmış filmlerde pürüzlü bir yüzeyin oluştuğu görüldü. CdTiO3 350oC derecede nanokristalin yapıdadır ve 550oC dereceye kadar buyotlarını korumaktadır. Kalsinasyonu başlatma sıcaklığının, daha az yan ürünle istenilen malzemenin sentezlemesi için önemli bir parametre olduğu gözlemlendi. Mezogözenekli CdTiO3 ince filmlerin, sentez koşullarına bağlı olarak 44 ile 79 m2/g aralığında yüzey alanına ve 0.10 ile 0.16 cm3/g aralığında gözenek hacmine sahip olduğu belirlendi. This thesis work focuses on the synthesis and characterization of mesoporous CdTiO3 thin films by using a salt-surfactant assembly, which is defined as molten salt assisted self-assembly (MASA) method. The MASA method is a proper process to fabricate mesoporous transparent thin films. The characterization of the calcined powder and fresh gel samples was made by using XRD, SEM, TEM, ATR-IR, N2 sorption and POM techniques. The preparation of a clear solution containing ethanol as solvent, [Cd(H2O)4](NO3)2, two different surfactants ((C16H33N(CH3)3)Br and EO20PO70EO20), titanium(IV)butoxide (Ti(OC4H9)4) as titania source and concentrated HNO3 as acid to prevent quick polymerization of titanium alkoxide is the first step for the synthesis of the desired material. The prepared clear solution is coated on the glass substrates to form a liquid crystalline mesophase by the hydrolyzed titania species and the molten salt by the guidance of surfactant domains. Upon the calcination of the fresh gel samples, mesoporous CdTiO3 material is formed. In scope of this thesis work, several parameters were changed to determine the optimum the salt uptake, acid amount, surfactant ratio, coating method and calcination path for the synthesis. Among dip coating, spin coating and drop casting methods, dip coating method gave better results to produce a material with less side products, which was mainly CdO. The amount of HNO3 added to the solution affects the homogeneity and stability of the prepared fresh films. Although changing the amount of HNO3 did not affect the surface area significantly, it was observed that addition of excess amount of acid resulted in an uneven surface on calcined films. CdTiO3 is nanocrystalline at 350oC and stable up to 550oC. The initial calcination temperature is an important parameter to synthesize a material with less side product. Mesoporous CdTiO3 displays 44 to 79 m2/g surface area and pore volume of 0.11 to 0.18 cm3/g depending on the synthesis conditions. 80

In the past decade, the surprising magnetic behavior of gold nanoparticles has been reported. This unexpected property is mainly attributed both to size and surface effects. Mesoporous thin films are ideal matrices for metallic nanoparticles inclusion, because of their highly accessible and tailorable pore systems that lead to completely tunable chemical environments. Exploiting these features, we synthesized Au nanoparticles within mesoporous titania thin films (film thickness of ∼150 nm and pore diameter of ∼5 nm), and we studied their magnetic properties under confinement. Here, we present the results of the magnetization as a function of temperature and magnetic field for this system, which are consistent with the previously reported for free (unconfined) thiol-capped gold nanoparticles. The successful inclusion of stable magnetic Au nanoparticles within transparent mesoporous thin films opens the gates for the application of these nanocomposites in two-dimensional (2D) microdevices technology and magneto-optical devices. Fil: Granja, Leticia Paula. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martínez, Eduardo David. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina Fil: Troiani, Horacio Esteban. Comision Nacional de Energía Atómica. Gerencia de Área Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Bariloche). División Física de Metales; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sanchez, Clément. Centre National de la Recherche Scientifique; Francia Fil: Soler Illia, Galo Juan de Avila Arturo. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Mezogözenekli geçiş metal oksitlerinin üretilmesi birçok enerji ile ilgili teknolojilerin gelişmesinde önemlidir. Eriyik tuz yardımlı kendiliğinden oluşma (EYKO) metodu, birkaç basit aşamadan oluşur, bunlar başlangıç malzemelerinin (uygun tuz, yüzeyaktifler, setiltirimethilamonyum bromür, (CTAB) ve 10-löril eter, C12H25(OCH2CH2)10OH, ve su veya etanol) şeffaf çözeltisinin hazırlaması, bu çözeltinin herhangi bir alttaşa kapladıktan sonra yakılmasını içerir. Mezogözenekli geçiş metal oksit ince filmleri ve CdSe TiO2 foto-anotları, EYKO metodu ile üretildi ve birçok analitik teknik ile karakterize edildi. Tezin ilk bölümünde, CdSe/TiO2 ince filmi, mezogözenekli CdTiO3 ile H2Se gazının reaksiyona girmesi sonucu üretildi. Sentez basamakları her aşamada optimize edildi. Film kalınlığı, yakma sıcaklığı ve H2Se tepkime ortamı optimum koşulları bulmak için değiştirildi ve kuantum nokta duyarlı güneş pilleri üzerindeki etkisi incelendi. Fakat, mezogözenekli CdTiO3 ile H2Se gazının tepkimesinin verimsiz olduğu belirlendi veayrıca, metalik selenyum yan ürünü oluştuğu belirlendi. Verimlilik probleminden dolayı, mezogözenekli CdO-SiO2 (meso-CdO-SiO2 olarak adlandırıldı) ince filmleri, CdSe duyarlı TiO2 foto-anodunda daha çok duyarlı CdSe nanoparçacıkları oluşturmak için, sentezlendi. Fakat bu filmler silikanın yalıtkan olmasından dolayı güneş pilleri için uygun değildir. Tezin ikinci kısmı, başlangıç MASA çözeltisinin, (uygun tuz, yüzeyaktifler (CTAB ve 10-löril eter) etanol ve silika kaynağı Si(OCH3)4 veya titania kaynağı Ti(OC4H9)4) önceden hazırlanmış mezogözenekli TiO2 (meso-P25 olarak adlandırıldı) filmine eklenmesini içerir. Sonraki aşamalarda, filmler yakılır ve H2Se tepkimesi sonucu foto-anotlar elde edildi. Sentez parametreleri optimize edildi ve elde edilen bu malzemeler XRD, FTIR, Raman, 29Si-MAS-NMR, EXAFS, XANES, SEM, TEM, N2-sorplama teknikleri kullanılarak karakterize edildi. Başlangıçta yoğun çözelti kullanması, meso-P25 filminin içerisini homojen kaplarken, üzerinde de yalıtkan CdO-SiO2 filmini oluştuğu gözlendi. Dolayısıyla, meso-P25 filminin boşlukları içerisine yeterli CdSe-SiO2 film tabakası oluşturmak için seyreltik çözelti kullanıldı ve birkaç yükleme ile hedefe ulaşıldı. H2Se reaksiyon ortamı ve tepkime sıcaklığı optimize edildi. Ayrıca, CdO-SiO2 filim tabakasındaki silika miktarı sistematik azaltılarak incelendi. Üçüncü kısımda ise EYKO metodu mezogözenekli geçiş metal oksit ince filmlerini sentezlemek için uyarlandı. İlk olarak, mezogözenekli demir oksit ince filmleri EYKO metot ile sentezlendi ve yukarıdaki teknikler kulllanarak karakterize edildi. [Fe(H2O)6](NO3)3 ve CTAB ve 10-löril eter sisteminin termal ve yapısal özellikleri daha düzenli mezogözenekli Fe2O3 filmi elde edebilmek için incelendi. Yakma sıcaklığının, kristalleşme ve gözenekli yapı üzerindeki etkisi TEM, SEM, XRD and N2 sorplama teknikleri ile detaylı şekilde incelendi. Sonra, diğer mezogözenekli geçiş metal oksitleri (ZnO, CuO, NiO, Co3O4 and Mn2O3) EYKO metot kullanılarak sentezlendi. Başlangıçta bilinen geçiş metali nitrat tuzları ([Zn(H2O)6](NO3)2, [Cu(H2O)6](NO3)2, [Ni(H2O)6](NO3)2, [Co(H2O)6](NO3)2, [Mn(H2O)6](NO3)2) ve yüzey aktif arafazları kullanıldı. Sıvı kristal arafaz oluştuktan sonra farklı sıcaklıkta yakılarak ince filmler elde edildi. Sentezlenen mezogözenekli gecis metal oksit ince filmlerini, yukarıdaki analitik teknikler kulllanarak karakterize edildi. Fabrication of mesoporous transition metal oxide thin films are important for the development of many energy related technologies. Molten salt-assisted-selfassembly (MASA) method, that has simple stages such as preparation of a clear solution of the precursors in water or ethanol, coating of this solution on a substrate as a thin film, and calcination of the film at an elevated temperature is a simple and useful method to fabricate mesoporous thin films. In this thesis, mesoporous transition metal oxides thin films and CdSe sensitized TiO2 photoanodes have been fabricated using MASA approach and characterized using multi-analytical techniques. In the first part of the thesis, CdSe/TiO2 thin films were synthesized by reacting mesoporous CdTiO3 thin film under a H2Se gas atmosphere. Many synthesis parameters were optimized in the synthesis of mesoporous CdTiO3 thin films. The film thickness, calcination temperature, and H2Se reaction condition have been changed to determine the optimum synthesis conditions for an efficient photoanode of a quantum dot sensitized solar cell (QDSSC). However, the reactivity of CdTiO3 towards to H2Se gas is low and selenium forms as a side product upon H2Se reaction. For the reactivity problem, mesoporous CdO-SiO2 (denoted as mesoCdO-SiO2) thin films were synthesized to increase the CdSe nanoparticle population, as the sensitizer in the CdSe sensitized TiO2 photoanode. However, The meso-CdSe-SiO2 thin films are not active in solar cells because of an insulating nature of silica. Second part of the thesis involves infiltration of MASA solution (precursors of saltsurfactant and a polymerizing agent, such as Si(OCH3)4 or Ti(OC4H9)4) into the pore of prefabricated films (using P25) of mesoporous titania (denoted as meso-P25). In latter steps, the above films were calcined and then reacted under H2Se to obtain the photoanodes (denoted meso-CdSe-SiO2-P25 and meso-CdSe-TiO2-P25). The synthesis conditions were optimized by changing the synthesis parameters (such as precursor concentrations, calcination, and H2Se reaction temperatures) and using XRD, FTIR, Raman, 29Si-MAS-NMR, EXAFS, XANES, SEM, TEM, N2-sorption techniques. However, formation of a meso-CdO-SiO2 thin film, on top of the mesoP25 film, was observed upon using a concentrated MASA solution in the infiltration step. Therefore, multiple loading method has been established to increase the CdSeSiO2 layer in the pores of meso-P25 using diluter MASA solutions. Also, the H2Se reaction conditions were optimized by controlling the reaction atmosphere and temperature. Effects of silica amount in the CdO-SiO2 system on the photoanode has been examined by measuring the I-V curves, of the solar cells fabricated using our photoanodes. In the last part of the thesis, the MASA method has been adopted for the synthesis of mesoporous transition metal oxides thin films. Firstly, mesoporous iron oxide film has been synthesized using MASA approach and characterized using above analytical tools. The thermal and structural properties of the [Fe(H2O)6](NO3)3/surfactants (10-lauryl ether and CTAB) mesophases have been investigated for the synthesis of a well-ordered iron oxide films. Effects of calcination temperature, on the crystallinity, and porosity of mesoporous Fe2O3, have been demonstrated by using TEM, SEM, XRD, and N2 sorption techniques. Later, other mesoporous transition metal oxides (such as ZnO, CuO, NiO, Co3O4 and Mn2O3) have been synthesized using the MASA approach. The transition metal salts ([Zn(H2O)6](NO3)2, [Cu(H2O)6](NO3)2, [Ni(H2O)6](NO3)2, [Co(H2O)6](NO3)2, [Mn(H2O)6](NO3)2)-surfactant mesophases have been used as the starting liquid crystalline materials that can be calcined at high temperatures (above 300 °C) to obtain the thin films. The synthesized mesoporous metal oxide thin films were characterized by using above analytical tools. 105

The past decade has seen significant progresses in the ability to fabricate new mesoporous thin films with highly controlled pore systems and emerging applications in sensing, electrical and thermal isolation, microfluidics, solar cells engineering, energy storage, and catalysis. Heat management at the micro- and nanoscale is a key issue in most of these applications, requiring a complete thermal characterization of the films that is commonly performed using electrical methods. Here, plasmonic-induced heating (through Au NPs) is combined with Tb3+/Eu3+ luminescence thermometry to measure the thermal conductivity of silica and titania mesoporous nanolayers. This innovative method yields values in accord with those measured by the evasive and destructive conventional 3ω-electrical method, simultaneously overcoming their main limitations, for example, a mandatory deposition of additional isolating and metal layers over the films and the previous knowledge of the thermal contact resistance between the heating and the mesoporous layers. Fil: Brites, Carlos D. S.. Universidade de Aveiro; Portugal Fil: Fuertes, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina Fil: Angelome, Paula Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina Fil: Martínez, Eduardo David. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina Fil: Lima, Patrícia P.. Universidade de Aveiro; Portugal Fil: Soler Illia, Galo Juan de Avila Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina Fil: Carlos, Luís D.. Universidade de Aveiro; Portugal

A scalable, simple, robust and reproducible method is presented for the preparation of chemically homogeneous and ordered nanocrystalline and mesoporous Zr1-xCexO2 thin films. The method utilizes widely available commercial block copolymers as templates. We show how the preparation conditions, film compositions and thermal treatments determine the mesoporous and crystalline structure. Through the scanning of the synthetic process, it was possible to arrive at an optimized and very reproducible method which allows the preparation of high quality, transparent, nanocrystalline and ordered Zr1-xCexO2 mesoporous thin films with different compositions. Fil: Violi, Ianina Lucila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina Fil: Luca, Vittorio. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina Fil: Soldati, Analía Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Troiani, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Soler Illia, Galo Juan de Avila Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área Investigaciones y Aplicaciones no Nucleares; Argentina. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina Fil: Zelcer, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Bionanociencias "Elizabeth Jares Erijman"; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina

A versatile bioelectronic system is presented, based on Ag nanoparticle assemblies embedded into hierarchically mesoporous titania thin films on which electroactive enzymes are simply immobilized by a fast adsorption process. This strategy enables straightforward, cost effective, high-performance, thin-film enzymatic fuel cell technology with foreseeable applications in self-powered microfluidic and electronic Fil: Bellino, Martin Gonzalo. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Soler Illia, Galo Juan de Avila Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; Argentina